Fixing the Delta is critical

Now in a third year of drought, Southern Californians are once again facing the realities of living in a region with variable and unpredictable rainfall. Voluntary rationing, increased water rates and a proliferation of water-use restrictions are the order of the day. This is an opportunity for residents to achieve durable gains in water conservation. One key to resolving the state's biggest long-term water crisis: fixing the Sacramento-San Joaquin Delta.

We believe there is a solution to the crisis in the Delta — the hub of the state's water supply and the focus of years of conflict — that balances the state's need for both a reliable water supply and a healthy ecosystem. But it's one that requires compromise. For Southern Californians and others who rely on Delta water supplies, it is likely to mean taking less water from this source in the future than they've gotten in the past.

The most recent flare-up in this troubled region began in 2004, when the populations of several key fish species crashed, including the endangered delta smelt. In 2007, the fish crisis became a water supply crisis: To protect the delta smelt, a federal judge restricted the operations of water export pumps at the Delta's southern edge. In 2008, he made a similar ruling to protect Chinook salmon. Yet the numbers have continued to tumble for smelt, salmon and other species, raising the specter of additional cutbacks. Compounding these environmental woes, the fragile levees that help keep Delta waters fresh face a high and increasing risk of failure from earthquakes and floods. A catastrophic failure of Delta levees could shut down the pumps for months or even years.

Southern California and the San Francisco Bay Area depend on the Delta pumps for nearly a third of their water supplies, and Delta water irrigates nearly a third of the farmland in the San Joaquin Valley. It is not surprising, then, that water managers in regions that rely on Delta exports are reacting to the crisis with a sense of urgency.

The solution water exporters have been pursuing, with the support of Gov. Arnold Schwarzenegger's administration, is to build a canal around the Delta to convey Sacramento River water to the pumps with less interference to native fish. The environmental review for this approach, which would also include significant ecosystem investments, is scheduled to be completed by 2010. Proponents hope that ground could be broken within several years, with the canal coming online in about a decade.

In broad strokes, the exporters' approach is consistent with the conclusions of our recent study of the Delta crisis. We found that ending water exports altogether would be the best prospect for native fish, but at significant cost to the state's economy. A peripheral canal around the Delta could improve conditions for the fish by allowing the return to more natural, variable flows in the Delta. The increasing demand for water by cities and farms has created a Delta in which water flows are often fatal to fish.

A canal would also be the least costly solution for water users, by reducing the threat of catastrophic levee failure and improving water quality for human use. In contrast, continuing to pump large volumes of water through the Delta is bad for the state's economy and is the worst alternative for native fish.

In 1982, Northern California voters overwhelmingly rejected a canal plan that already had the blessing of the Legislature, the governor and the federal government. The fears then — that the canal would permit a Southern California “water grab,” harming the environment and Northern California's economy — are still present today. But since that time, Southern California has become a much better steward of the state's water resources, with impressive gains in water conservation and improved use of local water resources.

Even if a canal is built, it is unlikely that as much water will move south in the future. Because native fish populations deteriorated over a period when water exports increased significantly, long-term export reductions will probably be needed to help bring the Delta ecosystem back to health. The health of fish and the volume of water exports also will depend on the successful expansion of fish habitat in the Delta.

Our analysis suggests that compromise is essential. Even with significantly reduced exports, a canal is still the best option for water users. The current drought provides Southern Californians with the opportunity to make progress in reducing water use — one key to living with the near-term drought and to finding a durable solution for the Delta.

Hanak is director of research and a senior fellow at the Public Policy Institute of California. Lund is a professor of environmental engineering and co-director of the Center for Watershed Sciences at UC Davis. Their full report is available at
ppic.org
.